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 Post subject: "The Alexandrite Effect"- lighting modes vs color change
PostPosted: Sat Aug 24, 2013 1:52 am 
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Hey folks,

I just wanted to share this very interesting, and very easy-to-understand, background behind the color change in alexandrite, how it works with relation to different lighting sources, and how to predict what color a stone will change back and forth between in different lighting conditions by examining the absorbance spectrum of the stone.

http://www.chemistry-blog.com/2013/08/2 ... ted-equal/


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 Post subject: Re: "The Alexandrite Effect"- lighting modes vs color change
PostPosted: Sat Aug 24, 2013 10:29 am 
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And and interesting article from G&G here in pdf:
Gemstones with the Alexandrite Effect by E. Gubelin and K.Schmetzer


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 Post subject: Re: "The Alexandrite Effect"- lighting modes vs color change
PostPosted: Sun Aug 25, 2013 1:56 pm 
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Very interesting article ! Thanks , Barbra !
I've yet never seen a real alexandrite , only virtual ones ...

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 Post subject: Re: "The Alexandrite Effect"- lighting modes vs color change
PostPosted: Mon Dec 23, 2013 9:52 am 
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I have a love for color changing gems which took me to Madagascar in 2001 for the Worlds finest alexandrite like garnets from Bekily. My concern for selling these color changing gems is how are we to see the red without the incandescent bulbs which are to be banned in the coming year. Will leds ever produce a comparable color. Halogens are ok but not as good as traditional incandescent bulbs.


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 Post subject: Re: "The Alexandrite Effect"- lighting modes vs color change
PostPosted: Mon Dec 23, 2013 12:04 pm 
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stmor wrote:
My concern for selling these color changing gems is how are we to see the red without the incandescent bulbs which are to be banned in the coming year. Will leds ever produce a comparable color. Halogens are ok but not as good as traditional incandescent bulbs.

Candle light. This probably isn't the answer you're seeking. But one should remember that Alexandrite was discovered and appreciated long before the incandescent light bulb was invented. The grand ladies of the Imperial Russian court had only the flickering light from candelabra to show off the gem's reddish hues.

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 Post subject: Re: "The Alexandrite Effect"- lighting modes vs color change
PostPosted: Mon Dec 23, 2013 12:37 pm 
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+1, ROM


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 Post subject: Re: "The Alexandrite Effect"- lighting modes vs color change
PostPosted: Sat Apr 19, 2014 5:08 am 
Rom, if i may step in the discussion, Ive been collecting alexandrite since 2005 & have a pendent that does as u say in candlelight & daylight, nice colorchange effect-m76... 8)
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